TTC PCOS. Getting discouraged and needing some advice

I’m starting to get discouraged. I found out in September 2019 that I have pcos. I was put on letrozole 2.5mg it hasn’t done nothing for me. I took a break and now af hasn’t showed her face this month and all pregnancy tests are coming out negative. Once AF shows I will be going back on letrozole but I just need some advice what else to try to improve anything.